ENES

Slack

A chat app for work, organized in channels instead of endless email threads.

A chat app window with a list of channels on the left, such as general, design and incidents, and a conversation on the right with messages, a thread and an automatic alert posted by a bot

Slack is a messaging app for teams. Instead of long email chains, conversations happen in channels named by topic or project, such as #design, #sales or #incidents, that anyone on the team can join, search and catch up on later. There are also direct messages, threads to keep side discussions tidy, quick voice and video calls, and file sharing.

It was born by accident. Stewart Butterfield's company was building an online game called Glitch and, to coordinate, the team had made an internal chat tool. The game failed, but the tool looked promising, and it launched as Slack in 2014. It spread fast among tech companies, partly because it was free to start and easy to try with a small team.

A big part of Slack's appeal is integrations. Other tools can post into channels: a build failing, a new sale, a server alert, a calendar reminder. Bots and AI assistants can answer questions there too. Salesforce bought Slack in a deal completed in 2021, and its main rival today is Microsoft Teams, which comes bundled with Microsoft 365.

Keep in mind

Go deeper

Related terms

More in Tech companies